Typograffiti.Cache

This module provides a method of caching rendererd text, making it suitable for interactive rendering. You can use the defaultCache or provide your own.

Documentation

class Layout t where

Generic operations for text layout.

Methods

translate :: t -> V2 Float -> t

Instances

Layout [TextTransform]

Defined in Typograffiti.Cache

Methods

translate :: [TextTransform] -> V2 Float -> [TextTransform]

data AllocatedRendering t

Holds an allocated draw function for some amount of text. The function takes one parameter that can be used to transform the text in various ways. This type is generic and can be used to take advantage of your own font rendering shaders.

Constructors

AllocatedRendering

Fields

• arDraw :: t -> V2 Int -> IO ()

  Draw the text with some transformation in some monad.

• arRelease :: IO ()

  Release the allocated draw function in some monad.

• arSize :: V2 Int

  The size (in pixels) of the drawn text.

makeDrawGlyphs :: (MonadIO m, MonadError TypograffitiError m, MonadIO n, MonadFail n, MonadError TypograffitiError n) => m (Atlas -> [(GlyphInfo, GlyphPos)] -> n (AllocatedRendering [TextTransform]))

Constructs a callback for for computing the geometry for rendering given glyphs out of the given texture.

vertexShader :: ByteString

The GPU code to finalize the position of glyphs onscreen.

fragmentShader :: ByteString

The GPU code to composite the recoloured glyph into the output image.

data SpatialTransform

Geometrically transform the text.

Constructors

SpatialTransformTranslate (V2 Float)

Shift the text horizontally or vertically.

SpatialTransformScale (V2 Float)

Resize the text.

SpatialTransformRotate Float

Enlarge the text.

SpatialTransformSkew Float

Skew the text, approximating italics (or rather obliques).

SpatialTransform (M44 Float)

Apply an arbitrary matrix transform to the text.

data TextTransform

Modify the rendered text.

Constructors

TextTransformMultiply (V4 Float)

Adjust the colour of the rendered text.

TextTransformSpatial SpatialTransform

Adjust the position of the rendered text.

Instances

Layout [TextTransform]

Defined in Typograffiti.Cache

Methods

translate :: [TextTransform] -> V2 Float -> [TextTransform]

transformToUniforms :: [TextTransform] -> (M44 Float, V4 Float)

Convert the TextTransforms into data that can be sent to the GPU.

move :: Float -> Float -> TextTransform

Shift the text horizontally or vertically.

scale :: Float -> Float -> TextTransform

Resize the text.

rotate :: Float -> TextTransform

Rotate the text.

skew :: Float -> TextTransform

matrix :: M44 Float -> TextTransform

color :: Float -> Float -> Float -> Float -> TextTransform

Recolour the text.

alpha :: Float -> TextTransform

Make the text semi-transparant.

liftGL :: (MonadIO m, MonadError TypograffitiError m) => m (Either String a) -> m a

Utility for calling OpenGL APIs in a error monad.